Apparatus for making magnetic material



April 16, 1968 -J. R. IRELAND APPARATUS FOR MAKING MAGNETIC MATERIALFiled Nov. 16, 1964 M T 1 I l INVENTOR. JAMES E /e-4A/0 United StatesPatent 3,377,651 APPARATUS FOR MAKING MAGNETIC MATERIAL James R.Ireland, RR. 2, Smoke Road, Valparaiso, Ind. 46383 Filed Nov. 16, 1964,Ser. No. 411,454 Claims. (Cl. 18-1) ABSTRACT OF THE DISCLOSURE Ferritecrystals and crystal fragments are removed from a slurry containingcrystals, crystal fragments and fluid by feeding said slurry upwardlyinto a nip region formed between a pair of magnetic rollers or pulleyshaving parallel axes. Conveyors passing around the magnetic rollersconvey the magnetic material attracted to the rollers or pulleys throughthe nip region wherein the magnetic material is magnetically oriented.The conveyors then convey said material away from the nip region forfurther processing.

This invention relates to an apparatus for removing ferrite crystals andcrystal fragments from a slurry containing crystals, crystal fragmentsand fluid and subsequently magnetically orientating the ferrite crystalsand crystal fragments to form a desired grade of magnetic granule.

In the process of manufacturing certain ceramic magnetic grades, such asindicated empirically by MO-nFe O of which BaO-6Fe O and PbO-6Fe O arespecific examples, it is desired to produce granules of predeterminedsize consisting of a multitude of hexagonal ferrite crystals or crystalfragments. Furthermore, it is desired that each ceramic magnetic granulehave all the crystals associated therewith magnetically aligned inparallel relation to each other.

One well known method of producing ceramic magnetic granules is to placea slurry, consisting of crystals, crystal fragments and water, into aform in which there exists a magnetic field of suflicient intensity tomagnetically orient the crystals in parallel fashion. After magneticallyorienting the crystals, the slurry is then pressed to remove the watercontent while retaining the ceramic magnetic material in the form. Theresulting ceramic compound may then be broken up into granules of thedesired size.

The foregoing method of producing ceramic magnetic granules is expensiveand time consuming since it requires a suitable press and pressoperator, and the pressing operation itself is inherently slow. Tofurther increase the expense of the foregoing method, a sufiicientnumber of forms are required so that continuous production of ceramicmagnetic granules can be had.

It is therefore an important object of the present invention to providemeans for simultaneously removing a substantial quantity of waterassociated with ferrite crystals in a slurry and magnetically orientingthe crystals which form magnetic granules.

Another object of the present invention is to provide a pair of magneticpulleys for removing ferrite crystals and crystal fragments from aslurry.

Still another object of the present invention is to provide means forquickly removing a substantial quantity of water from a slurry whileleaving a small quantity of water behind which can be quickly removed bydrying heat.

A further object, and one of considerable importance from a commercialstandpoint, resides in the provision of a continuous means for removingcrystals and crystal fragments from a slurry which is completelyautomatic and does not require a full-time operator.

3,377,651 Patented Apr. 16, 1968 Yet another object of the presentinvention is to provide means for magnetically orienting ferritecrystals and crystal fragments as they pass through a magnetic pulleyassembly.

Further objects of this invention as well as a better understandingthereof, may be had from the following description when considered inconjunction with the accompanying drawings in which:

FIGURE 1 is a side elevational view of a preferred apparatus inaccordance with the present invention for removing crystals and crystalfragments from a slurry; and

FIGURE 2 is a top plan view of the apparatus shown in FIGURE 1, showingan alternative means for driving said apparatus.

The apparatus shown in FIGURE 1 is generally designated by referencenumeral 10 and has particular utility when used to remove magneticparticles from a slurry containing, by way of example, ferrite crystals,crystal fragments and water. However, it will be understood that theapparatus 10 can be used to remove any magnetic particle from a compoundof magnetic and non-magnetic particles.

A pair of magnetic rollers 12 and 13 have their axes in a parallelrelation and lying in a common plane. Rollers 16 and 17 have their axesin parallel relation with each other and in parallel relation withmagnetic rollers 12 and 13, and lying in the same plane. Wrapped aboutthe magnetic roller 12 and idler roller 16 is a flexible conveyor belt20, and wrapped about the magnetic roller 13 and driven roller 17 is aflexible conveyor belt 21. A motor 23 is provided with a pulley 24 fortransmitting rotational movement to a pulley 25 via belt 26. Roller 17has an extended shaft portion 28 which has secured thereto pulley 25.The continuously moving contact area between the conveyor belts 20 and21 is herein defined as a nip region.

The tension of web 21 between the magnetic roller 13 and the roller 17is sufficient to cause magnetic roller 13 to rotate as the roller 17 isdriven. As shown at 30, the magnetic rollers 12 and 13 have a contactingZone which provides sufiicient friction to transmit rotating motion fromthe magnetic roller 13 to magnetic roller 12, and therefrom via theconveyor belt 20 to idler roller 16.

In operation, the slurry designated by reference numeral 32 is fed tothe input side of the contacting zone 30 by slurry feeding means 33.Since the rollers 12 and 13 and Conveyor belt 23 and 21 are rotating inthe direction as indicated at 35, the slurry 32 will be drawn throughthe contacting Zone 30 to the output thereof. This action will cause asubstantial quantity of water to fall away by gravitational force whilethe magnetic particles are drawn toward the magnetic pulley at thecontacting zone 30. A further substantial quantity of water is removedfrom the slurry 32 by a wringcr or pressing action between thecontacting surfaces of conveyor belts 20 and 21 allowing the magneticparticles to pass through the contacting Zone 30 in a substantially drystate. Magnetic particles which have been extracted from slurry 32 willcontinue to adhere to conveyor belt 20 or 21 because of the magneticfield imposed therethrough by magnetic rollers 12 and 13. As theparticles which adhere to conveyor belt 26 and move thereupon past apoint indicated at 34, the magnetic attraction of magnetic roller 12 isremoved. The particles on conveyor belt 20 are then passed under asuitable heater 36 for removing any water which may still be associatedtherewith. A scraper 38 shown in FIG- URE 1 is provided to remove themagnetic particles from the conveyor belt 20 thereby producing thedesired ceramic magnetic granules.

In a similar manner, as the particles which adhere to conveyor belt 21move thereupon past a point indicated at 40, the magnetic attraction ofmagnetic roller 13 is removed. The particles on conveyor belt 21 arethen passed under a suitable heater 41 for removing any water which maystill be associated therewith. A scraper 42 shown in FIGURE 1 isprovided to remove the magnetic particles from conveyor belt 21 therebyproducing the desired ceramic magnetic granules.

As shown in FIGURES 1 and 2, magnetic roller 12 and idler roller 16 aremounted between a pair of supports 45 and 46 while magnetic roller 13and roller 17 are mounted between a pair of supports 47 and 4 8.Provided in supports 45 and 46 are slots 56* and 51 for receiving endshaft portions 53 and 54 which are journaled in bearing support caps 55and 56 respectively. Also provided in supports 45 and 46 are slots 58and 59 for receiving end shaft portions 61 and 62 which are journaled bymovable bearings 64 and 65 respectively. Movable bearing 64 is arrangedfor a slidable adjustment in a slot 66 which, in turn, is machined in anend support 67. Screws 68 may be provided to secure the end support 67to support 45. Secured to the movable bearing 64 is a threaded shaft 70which, in turn, passes through a bracket 71. An adjusting nut 72 isthreaded on the shaft 70 and extends beyond the bracket 71, while alocking nut 73 is threaded on the shaft 70 behind the bracket 71. In asimilar fashion, movable bearing 65 is slidably adjustable in a slot 76which slot is machined in an end support 77. Connected to movablebearing 65 is a threaded shaft 79 the free end of which passes through abracket 80. Threaded on the shaft 79 is an adjusting nut 82 whichextends beyond the bracket 80, while also threaded on the shaft 79 is alocking nut 83 which is behind the bracket 80.

To adjust the tightness of conveyor belt 20, the end shaft portions 61and 62 of idler roller 16 are moved in the slots 58 and 59 by applyingtension to movable bearings 64 and 65. This is accomplished by turningnuts 72 and 82 on shafts 70 and 79 respectively to bring the idlerroller 16 toward the brackets 71 and 80.

Magnetic roller 13 and driven roller 17 are secured in substantially thesame manner as magnetic roller 12 and idler roller 16 and havesubstantially the same means of adjustment for conveyor belt 21.

Supports 45, 46, 4'7 and 48 are secured to a base by screws or by asuitable welding operation. A motor mounting block 83 is secured to thebase 85 by fasteners 89 and 90. Motor 23 is then secured to motormounting block 88 by fasteners 92 and 93.

The rollers 12 and 13 are constructed and arranged by placing axiallymagnetized permanent magnet disks 95 of annular configuration and steelpole piece disks 96 of annular configuration alternately on a shaftportion 97, and securing the magnets 95 and pole pieces 96 in place by apair of end plates 100 and 101. The magnets 95 may be lesser diameterthan the pole pieces 96 thereby providing recessed portions 102 whichmay be filled with a non-magnetic material such as epoxy. The magnets 95on either side of each of the pole pieces 96 are arranged so that a polesurface of each of the magnets is in contact with the flat surface atthe adjoining side of the pole piece 96. The permanent magnets alternatein polarity along the shaft so that the pole pieces 96 are of alternatepolarity as indicated in FIGURE 2.

As shown in FIGURE 2, the magnets 95 may be alternated with the polepieces 96 over the entire length of the roller 12 to provide asufliciently large surface to act as a magnetic pulley. The alternatenorth and south poles along the axis of roller 12 are constructed andarranged so that as the rollers 12 and 13 rotate as indicated at 35,FIGURE 1, each magnetic pole piece of roller 12 will be opposed at thecontact zone 30 by a magnetic pole piece of opposite polarity of theroller 13. However, it may be desired to mechanically synchronize therollers 12 and 13 by applying rotating motion thereto from a motorthrough a synchronized gear train 111, as shown in FIG- URE 2.

Summary of operation A pair of magnetic rollers 12 and 13 are rotated ina direction 35 as shown in FIGURE 1. Wrapped about rollers 12 and 13 androtated therewith are conveyor belts 20 and 21 respectively. As a slurry32, consisting of ferrite crystals, crystal fragments and water, isapplied to an input side of a contacting zone 30, which exists betweenthe conveyor belts 20 and 21, the ferrite crystals are attracted towardthe contacting zone 30 by a magnetic field afforded therebetween bymagnetic rollers 12 and 13. In so attracting the ferrite crystals upwardtoward the contacting zone 30, a substantial quantity of waterassociated with the slurry 32 will fall away due to gravitational force,while a still further substantial quantity of water will be removed asthe slurry passes through the contacting zone 30 and is subjected to awringing or squeezing action. The ferrite crystals which are attractedtoward the contacting zone 30 are magnetically oriented in parallelfashion to each other to form magnetic particles which continue toadhere to conveyor belts 20 and 21 due to the magnetic fields of rollers12 and 13. After the magnetic particles are conveyed past apredetermined point on each conveyor belt 20 and 21, heat is appliedthereto to remove any water which may still be associated with themagnetic particles. As the magnetic particles are conveyed further byconveyor belts 2t) and 21, they are removed therefrom by scrapers 38 and42 respectively to producing the desired ceramic magnetic granules.

Although the description has been given with respect to a particularembodiment, it is not to be construed in a limiting sense. As mentionedhereinabove, both rollers 12 and 13 are magnetic and of similarconstrction; however, either roller 12 or 13 may be replaced by anonmagnetic roller or by a demagnetized ferrous roller. The foregoingdescription of this invention concerns only the preferred embodimentthereof, and accordingly, changes and modifications may be made thereinby those skilled in the art without departing from the spirit and scopeof the novel concepts of this invention.

I claim as my invention:

1. Apparatus for treating magnetic material in a slurry comprising,

a pair of substantially horizontally disposed rollers mounted forrotation on substantially parallel axes, conveyor means for movementalong an arcuate conveyor path about the axis of one of the rollers, thearcuate conveyor path extending between said rollers with the conveyormoving in an upward direction along said arcuate conveyor path,

said rollers providing a nip region along said arcuate conveyor pathwith an input region in advance of and below said nip region and anoutput region beyond and above said nip region along the arcuateconveyor path, and

slurry feeding means for directing said slurry into said input region,and

means for tending to hold magnetic material against said conveyor meansfor passage through said nip region while accommodating removal ofliquid by gravity and by a squeezing action of said rollers at said nipregion.

2. A system for treating magnetic material in a slurry comprising,

a pair of substantially horizontally disposed magnetic pulleys mountedfor rotation on substantially parallel axes and providing a nip regiontherebetween, the pulleys providing a magnetic field in the directionbetween the pulleys and through the nip region,

conveyor means extending about the peripheries of respective pulleys andtravelling in an upward direction at said nip region therebetween, and

means for supplying the slurry as an upwardly directed stream impingingon the conveyor means at the lower side of said nip region with thepulleys serving to attract magnetic material of the slurry to theconveyor 5 6 means for movement through the nip region while 4. Thesystem of claim 3 with the magnetic rollers havliquid is squeezedtherefrom at the nip region. ing annular pole faces of opposite magneticpolarity dis- 3. A system for treating magnetic material in a slurryposed in confronting relation at opposite sides of said comprising, nipregion to provide a magnetic field in the direction a pair of magneticrollers having parallel axes and de- 5 through said nip region.

fining a nip region therebetween, 5. The system of claim 3 with meansfor synchronizing a pair of idler rollers having axes parallel to theaxes of the rotation of said magnetic rollers so that said conveyors themagnetic rollers, travel at the same surface speed at said nip region. afirst continuous web wrapped about one of said magnetic rollers and oneof said idler rollers to provide a References Cited first coinveyotr, bd b t th th 10 UNITED STATES PATENTS a secon con muons we wrappe a on e0 er of said magnetic rollers and the other of said idler 3 2 12/1959Fnts ch XR rollers to provide a second conveyor, 6/1962 4 drive meansfor rotating said magnetic rollers and said 15 2,095,262 6/1963 Malsh et18 9 XR idler rollers to move said conveyors in an upward di- 331736111/1965 Ryan et rection through said nip region, and 3,228,052 1/ 1966Claus slurry feeding means for applying the slurry to said conveyors atthe region below said nip region for attrac- FOREIGN PATENTS tion ofmagnetic material in the slurry to the con- 20 519,576 3/1931 Germany.veyors and movement through said nip region While liquid of the slurryis squeezed from the magnetic WILLIAM J. STEPHENSON, Primary Examiner.material at the nip region.

